Oscillating edge grinder



-. y 9, 1956 G. F. RlTTER 2,747,342

OSCILLATING EDGE GRINDER Filed Dec. 27. 1951 3 Sheets-Sheet 1 3nventor 1 I I /& ej f Qdtac jag-2 Z WK W May 29, 1956 e. F. RIITTER 2,747,342

OSCILLA'IING EDGE GRINDER Filed Dec. 27. 1951 3 Sheets-Sheet 2 51 '11 k 4o 7 y 1/ 12,52 39 56 37 15 as I F as v A x l I as a Z1 41 54 i 14 M a attorney};

y 1956 s. F. RITTER 2,747,342

OSCILLATING EDGE GRINDER 5 Sheets-Sheet 3 Filed Dec. 27. 1951 3nnentor Gttotnegg United States Patent Themesen v n ent o el te broadly to improvement in ,ab zading appa atu ,aa ml i qi arl tofthe gr nd n en p hinao ima es Qffsh ets .orlpl s of gla ssorothetimaterials. H V

I Ii Y st t t n en on ntemp a th tow n g lrlg l/orfinishing of shapedegiges on sheets or plates by ca lia ne devic to t ave th ough -path p the same contour as th sh pe. f the ed ei b tonne? and/0r ni he F example, ac rding to theinvenitiomar lm dg can be emand .ona a as plat y sensin a rota y abrasive ev redrmcatipgthroagh a uate path, t t ave across an j n contact with the iil atewedge.

he p mar objec o t i in e tian i 1 ro ide an mprlo ed a ding devic ecig nhe tsiw thahrasiye he ls. vhe z=.i v he edgia s r ae 9 th z filisfifi moved k and ,fiqrt a q t shee ,e g by mean of an latingsqrport ther for.

Ano he bj c o the i ent n i t P Qvide e p o ed .d yi e of jthis nature wherei the ncrement .Qf "th rsd inet ur aees o ,t casbras tsi o suc 2 7131- r a -t ollqwd p thcoinciding o ganelle t ed. s ntqu o thesheeti de .rA ,v nrther objec o the inv nt o i t pmyide, n device of this nature, novel means for in'iparting osci lilatar mo em n to. heisup on i pameaaa r. the ab asi 'ib lt- ,-,Q; ,1 ob e and adva tage o thi .iinr nt gn wil be ome more. apparen du n 1 i i deser pt oni whe taken U n p n ine drawin n t e i 'rawing ilwhs ein lik m neral ar em larsd t desi at iki art th 1 h9u ame Fig. 1 is a front elevation of an edging deyi ce ernhodyth ii emi n;

2 a -enlar ed ir niqnv ary seetian tak n-sabn M sit r al o l n ,2:- .9 J

'1 he s cfiaa' Y. w t I p iFi E 4 is a siskel bn viewed ra vthe, r ht. a Fi .2 show n e ed n d s nd. ts at bns ip .Wit a v iir art n a d 99' vex ng msshamsrn;

ar sem final r c fiek substan ia ly vi -i a lg: is aseciional view talgen suhs tan tia llypn line .l 9 i -I .F g- 7 s? a pl view rar l i ti i naw empathy i i men fi -v.8 i frasm mat x a i ewl pk gg i he ye t pa fit e a my? in; ia-A n e othlq drawiassaa pa tisala ly t i aken su hsta ntially on vline -2 carriage 12 travels overthe framework lfl rneans of an e -wh ls firwh l a l 11 A k e e plate lfl to b edged is snpp rted in a:h iz ta positiqn 4 29. said. a r s1 n {is held eew el th e 9, sh a y sui b e me ns s sh l m s umb .14 .is s cn upon the carria ..1.,. 1in su ;h-?=-W t at-i will be moved past the edging,der1ice l3 with' an ed ge thereof in engagement with the 'rnoyingabrasiyeabelt 3S v g lb rh r in erdesc ihe n Th ed ing device 1 S p i i ee erally Q twp ast nme si suppmwt n t eer d es i br fls r q lt and (21) me n fo mparting 9 ato mov as t sugporting neans for said b elts. 'I fhe {former is f ted ubs a t a l pu d an .th f atte abslamia ia ides i i ar t tramews k .16 w adan srl ar/:8 on a flat surface '17. The fra n ework 16 'cqrnpr ises a lia q at fi saace pri ht 5 qo l ctedadia ent' heir upperendsfby a Weblfl. The front and ijack 91f t e fr e ar t a pen th ,,a sh wny iF igthe ifra rr ework is substantially U s'haped in .cross sec on. Th Wri ht i firaw rs rcqn' s pl e sa sta 1 r p z id -i sh iae exqerti e se .l tfifi 411 th t w r s'd e g i an di a th i ur e w adsr e la min Fi M 1 ed n ppara u i d ire by ajdi e shaf 2 paerative r d tham ta h W l h i eh a r ws r ra m t n m nsla n e 1 lan ,a ls i l i ,mi einas rsd 1 .sha a t erme i he p ieh A W l ie een th -dr shaft?) iq1 m e .in.lz a

s e Pl t 5 s s fie LI Y ,a fisht J1 amine it ax projecting beyond said plates to receive driving rollers gfi, Wh ske eye t e e dn d h i qutw xl of and lsp aced irom said uprights. Traine'd about and gfricti l t l e a le aq Q ot o le i a .endlea as a l fi aa h l 'bs im v raa it -it respectiye rqller 2 6 d11 6 'i 0 the trictional enga gen ent therewith. The particular'tmeof ahra sivejlgelt's or abrasive material used on said belts :depends, of cm rse upQn the WM of edge t ob e abraded. -rw tany carried uponjheinsidesurfaces of uprights 19 are substantially "Vertical-"lever arms 2 9 pivotedjat,'their lower ends to said -uprig'htsgas Bat 30. Carriedat the upper ends of arms-29 and extendingoutwardly therefrom are stub shafts 31 which rotatably support idler T-rol1ers'32. "As -best shown fin=fFig. '1,;each of the idler rollers=32 is in vertical alignment with its :respectirge driving roller 26 and horizontally parallel therewith. gEach of the -abrasire be1ts-28 extends upwardly from grollergo and is traine d over roller 32 andlresiliently tensionefl thereby; Y

.Tofeffect the desired "tensioning of the abrasive belts,

there issecured to -the upper end of each of thedfiyer arms-29 adjacent stub shaftfil a-flatarrn '34, through the end of which is -=threaded an adjusting screw 35. A coil spring 36 is-held in compression between a cylindrical protuberance 37 on a flanged end -38 of said adjustingscrew; and a-similar protuberance 39 on angle "bar 40 fsecured -to web 2 .0 of the supporting 'frarnework. Thus each of the idler rollers 32 is -l1e 1d resiliently against its respective abrasive *belt 28. Nuts 41 are threaded -upon' adjustingscrewBSat opposite sides of each arm 34 such that the tension of rollers 32 against bel-ts -28 ma-yfbe adjusted bymanua1 manipulation of the adjusting screws.

The abrasive :ibelts 28 are also trained about guide rollers 42, which provide oscillating supportsthe'reior, in a manner-to be= hereinaiter described The guide rollers 42arerotatablysupported on opposite ends of ahorizonta-l shaft 43 iour-naledin-hubs -44-which extend outwardly from opposite sides of an oscillating frame outwardly from hubs 44 and beyond uprights 19 such that, as can be seen in Figs. 1 and 7, each of the guide rollers 42 is in vertical alignment with and horizontally parallel to its respective idler roller 32 and driving roller 26, and each provides a guide and support for that portion of its respective belt 28 which, in its rotation, is disposed in engagement with sheet 14. Improved results are obtained by making guide rollers 42 with a relatively hard core 46 of metal or similar material and a relatively soft, resilient outer layer 47 of rubber or the like (see Fig. 7). Also, rollers 26 and 32 may be grooved at 27 and 33, respectively.

The means for oscillating the abrasive belts is driven from the same source as the belt driving apparatus by means of a small sprocket 48 which is keyed to drive shaft 22 at a point between pulley 24 and one of the uprights 19. Driven by sprocket 48 is a chain 49 meshing with a relatively large sprocket t) keyed to a stub shaft 58 which is journaled in upright 19 and bearing plates 59. The sprocket 50 acts as a speed reducer for the oscillating frame 45. Meshing with the upper reach of chain 49 is a slack take-up mechanism, denoted generally as 51, comprising a pair of arms 52 and 53, each of which is keyed at one end to opposite ends of a horizontal spindle 54 journaled in the upright 19 adjacent small sprocket 48. Secured to the other end of arm 53 is a sprocket 55 and bearing against the opposite end of the other arm 52 is an adjusting screw 56. As best shown in Fig. 4, said adjusting screw 56 is disposed outside the upright 19 and is threadedly received in a bracket 57 secured to said upright in such a manner that it bears against one end of the rigid lever formed by arms 52 and 53 and spindle 54 so that, upon manual manipulation thereof, the slack in chain 49 can be ad- 'justed.

Eccentrically mounted on the inner face of sprocket 50 is an oscillating arm 60 having an eye 61 at its lower end pivoted as at 62 to a rectangular slide member 63 (Figs. 2 and 3) slidably mounted in a guideway 64 in a rectangular member 65 which is secured to the inner face of sprocket 50. Slide member 63 is slotted at 66 to accommodate bolts 67 for securernent to member 65. By means of the slot 66, the slide member can be adjusted longitudinally of rectangular member 65 so that the point of eccentricity on sprocket 50 and, consequently, the length of oscillatory movement of the arm 60 can be changed. Threaded upon the upper end of oscillating arm 60 is a block 68 which is pivotally mounted on a horizontal bar 69 at the lower end of frame 45. At the upper end of the frame is a similar horizontal bar 70. The bars 69 and 70 extend between side members 71 of the oscillating frame 45 and are parallel to webs 72, which add rigidity to the frame. Each of the side members is flanged at apoint adjacent recesses 21 and hubs 44 extend from said flanged portions through the recesses 21. It can now be seen that oscillating arm 60 imparts movement to the frame 45 and, thus, to guide rollers 42.

The extent of this movement is controlled by pivotal connections between stationary uprights 19 and upper and lower ends of movable frame 45. These pivotal connections are shown in detail in Figs. 5 and 6. There are two pairs of such connections, as best shown in Fig. 1, one of which connects the upper end of frame 45 to the upper ends of uprights 19 and the other the lower end of said frame to that portion of uprights 19 below recesses 21. Thus, frame 45 is hingedly supported by said pivotal connections and hubs 44 are oscillated by said frame within the openings defined by recesses 21.

Taking, by way of example, one of the upper pairs, it can be seen that the connection comprises a bifurcated member 73 the solid end 74 of which is pivotally mounted to one end of upper bar 70 which extends outwardly from side member 71. The opposite or forked end of member 73 is pivotally mounted upon upright 19 by means of shoulder bolt 75 which extends through a block 76, secured to said member 73, and a slot 77 in upright 19. Block 76 is secured to the legs of member 73 by means of a raised portion 78 thereon which is slidably received between said legs and held rigidly thereagainst by bolts 79. Shoulder bolt 75 holds flanged sleeves 80 adjacent upright 19 to provide a bearing surface upon which block 76 is pivotally mounted. It can now be seen that nut and washer 81 on the threaded end of shoulder bolt 75 may be loosened such that block 76 may be moved longitudinally with respect to the legs of member 73 and bolts 75 with respect to slot 77. In this manner, the degree of curvature of the arc traversed by upper bar 70 can be adjusted.

Broken lines 82 in Fig. 4 illustrate the upper and lower limits of movement of frame 45, bifurcated members 73, and abrasive belts 28, as the frame is oscillated in its arcuate path by arm 65). Shaft 43 and guide rollers 42 mounted thereon will be oscillated by said frame 45 in a limited path indicated by broken line 33, the limit to be determined by the relative location of pivot point 62 on sprocket 50 and the degree of oscillation to be dependent upon the relative location of shoulder bolt 75 with respect to bars 69 or 70. In moving in an arcuate path with roller 42, belts 28 will cause idler rollers 32, resiliently held against the belts, to swing in opposition to coil spring 36 in compensating for said arcuate movement.

With particular reference to Fig. 4, it will be seen that upon operation of the motor (not shown), belts 28 will be driven to provide a moving abrasive edging surface on guide rollers 42. At the same time, the rollers 42 will be oscillated through a vertically arcuate path, indicated by broken line 83. The mid position of the rollers is shown in solid lines so that it is apparent that the center of the arcuate path traversed by said rollers lies along a line 84 longitudinally of sheet 14 and centrally of the edge thereof. Consequently, the portion of belts 28 will be held against the sheet edge 85 by guide rollers 42 to create lines of contact between said belts and said edge, and these lines of contact will be constantly shifting from one side of the edge to the other through a path coinciding or parallel with the desired contour of the finished edge.

In grinding and finishing rounded edges on glass plates it is important to oscillate the guide rollers through a sufiicient lengthof are so as to carry the effective edging surfaces of the belts beyond the upper and lower planes of the sheet at the ends of the arc in order to avoid fiat portions on the finished edge. As previously noted, the length of arc traversed by the guide rollers 42 can be controlled by the adjustment of eccentric pivot point 62 on large sprocket 50.

The device of this invention has proven to be of especial utility in seaming the edges of laminated safety glass as well as in putting crown edges on heavy plate glass as indicated at 85 in Fig. 4. By way of example, in the latter process a glass sheet 14 is placed on carriage 12 and held secure by clamps 15. The carriage is then moved on track 11 past the edging device B in order to bring the sheet edges into successive engagement with one and then the other of belts 28. By use of the proper grit sizes of abrasive material, the edge will be ground down to a. crown by the first belt it passes, and said crown will be fine ground or polished as it passes in engagement with the second belt. Thus, an edge can be rough ground to shape and then finished by a single run of the sheet past the edging device. Additional edges of the sheet may be finished by turning the sheet on the carriage and returning it over the same path. Of course, it would be within the province of this invention to finish two edges simultaneously by the provision of a second edging device on the opposite side of carriage 12.

In the device as herein disclosed, a sufiicient amount of belts 28 are retained in contact with sheet 14 by .the

resilient outer layer on guide rollers 42, obviating the necessity for feeding the sheets themselves toward the device. However, whenever desirable, means for so feeding the sheets toward the device or, in the alternative, the device toward the sheets, may be provided without departing from the scope of this invention.

Also, it is contemplated that the endless abrading belts may be eliminated and rollers having abrasive edging surfaces substituted therefor.

It is to be understood that the form of the invention disclosed herein is to be taken as the preferred embodiment thereof, and the various changes in the shape, size and arrangement of parts may be restorted to without departing from the spirit of the invention or the scope of the following claims.

I claim:

1. In an edge treating device, a rigid framework, blocks pivotally attached to said framework, links connected at one end to said blocks, a mounting member pivotally connected to and supported by the opposite ends of said links so as to be movable in a predetermined oscillatory curved path with respect to said framework and said edge to be treated, adjustable attaching means connecting said links with said blocks and being adjustable to permit the effective length of said links between the pivotal connections of said links and the corresponding blocks therefor to be changed so as to correspondingly change the radius of curvature of said curved path, an edge grinding tool supported on said member intermediate the pivotal connections for said mounting member, and drive means for moving said mounting member in said oscillatory path and simultaneously moving the surface of said tool relative to said mounting member and in a direction substantially perpendicular to the edge to be treated.

2. In an edge treating device, a rigid framework, blocks pivotally attached to said framework, links connected at one end to said blocks, a mounting member pivotally connected to and supported by the opposite ends of said links so as to be movable in a predetermined oscillatory curved path having a radius of curvature determined by the distance between the pivots of said links and the blocks connected thereto with respect to said framework and said edge to be treated, adjustable attaching means connecting said links to said blocks and being adjustable to prevent the effective distance between the pivot of said links and the pivot of the corresponding blocks to be changed so as to correspondingly change the radius of the curvature of the oscillatory curved path, a guiding roller supported on and movable with said member intermediate the pivotal connections therefor, an abrading belt trained over said roller, means for supporting the edge to be treated in contact with said belt and opposite said roller, means for moving said mounting member in said oscillatory path to cause said belt to be urged by said roller to move in an oscillatory path over said edge, and drive means for moving said belt relative to said mounting member about an axis parallel to said edge.

3. In an edge treating device, a rigid framework, blocks pivotally attached to said framework, links connected at one end to said blocks, a mounting member pivotally connected to and supported by the opposite ends of said links so as to be movable in a predetermined arcuate path with respect to said framework and said edge to be treated, adjustable attaching means connecting said links to said block and being adjustable to permit the effective length of said links between the attaching means and the pivotal connections therefor to be changed so as to correspondingly change the radius of curvature of said arcuate path, an edge grinding tool supported on said mounting member intermediate the pivotal connections for said member, and drive means for moving said mounting member in substantially harmonic motion through said arcuate path and simultaneously moving the surface of said tool relative to said mounting member.

4. An edge treating device as defined in claim 3, in which the surface of the grinding tool is moved with respect to said mounting member in a direction substantially perpendicular to the edge to be treated.

5. In an edge treating device, a rigid framework, blocks pivotally attached to said framework, links connected at one end to said blocks, a mounting member pivotally connected to and supported by the opposite ends of said links so as to be movable in a predetermined arcuate path having a radius of curvature equal to the distance between the centers of pivot on said links and blocks with respect to said framework and said edge to be treated, adjustable attaching means connecting said links to said blocks and being adjustable to prevent the effective length of said links between the pivotal connections therefor and the attaching means to be changed so as to correspondingly change the radius of curvature of said arcuate path, an edge grinding tool supported on and movable with said member intermediate the pivotal connections for said mounting member, means for supporting the edge to be treated in contact with said tool, drive means for moving said mounting member in substantially harmonic motion along the arcuate path relative to said edge to be treated, and adjusting means on said drive means for varying the amplitude of harmonic motion of the mounting member.

References Cited in the file of this patent UNITED STATES PATENTS 165,762 Sawyer July 20, 1875 275,385 Howe Apr. 10, 1883 725,142 Robinson Apr. 14, 1903 737,393 Goehring et al. Aug. 25, 1903 1,365,583 Brown Jan. 11, 1921 1,689,829 Heintz Oct. 30, 1928 1,798,421 Hitchcock Mar. 31, 1931 2,192,240 Richardson Mar. 5, 1940 2,231,762 Johanson Feb. 11, 1941 2,433,427 Carlsson Dec. 30, 1947 2,467,978 Kerr et al. Apr. 19, 1949 2,470,221 Mott May 17, 1949 2,518,018 Jung Aug. 8, 1950 2,573,220 Riedesel et al. Oct. 30, 1951 2,621,449 Martin et al Dec. 16, 1952 

